OmNomNom - Mensa Bot
During my time at the university we had a Telegram group to organize lunch breaks and going to the canteen. Every day someone asked what was on the menu and someone else posted a link to one of the different websites of the different campus canteens. When Telegram published their bot API it was time to automate this, so the idea of the OmNomNom bot was born. OmNomNom is a Telegram bot that can tell you what you can eat in some canteens in Berlin (Germany), you can invite the bot to a group or ask it directly. What started as a simple Python script scraping two websites became a bigger project over the years, scraping about 50 cantens. During the week the bot serves roughly 100 menu requests each day, so even though I left the university, people still use it. The bot is open source and the code is available at GitHub. Just click here to start talking to OmNomNom.
Home Assistant Meetup Berlin
I am a fan of smart devices and home automation, but I am also a fan of privacy. Unfortunately, those interests very often contradict each other because a lot of companies produce smart devices that intrude the privacy of their customers instead of protecting it. Home Assistant is an amazing open source project that allows everyone to create their own smart home while keeping full control of their own data. To bring the community further together I started the Home Assistant Meetup Berlin in 2019 . When I moved away from Berlin I decided to hand over the organization of the meetup to another community member, so hopefully after the pandemic more meetups in Berlin will happen.
A friend and I developed PowerSwitch, an Android app to control power outlets that are remote controlled on a frequency of 443MHz. In the beginning this started as a small side project in the forum of one of the companies that was producing one of the wireless gateways. After a while the project gained so much traction that they politley asked us to move somewhere else because they started to get into trouble with some of their investors for "providing a platform for an alternative software". So we moved and made our own website, forum and Google+ community. For a few years the project had a very active community with thousands of forum posts and a lot of active users. We invested a lot of time in the app and it became quite the solid product with a lot of nice features. Actually, it went so well that one day our phone rang and a rather big company wanted talk about ways to partner up. The talks went on for a few months, but in the end it did not work out because they did not like that we wanted to publish everything as open source. Today, the app is not under active development anymore, but the source is still open at GitHub and the app is available in the Play Store with more than ten thousand installations.